Category: Life

Just Found Out: Yeonjoon Yoon’s Etudes: Triptych – Live Was Out + Life Update (26.8.3)

Hello, this is Jooyoung Kim, an audio engineer and music producer.

Recently, I’ve been busy conducting research related to Korean traditional musical instruments, which requires several listening tests. Therefore, I met Yeonjoon Yoon, a composer and pianist who has worked with some Korean traditional musicians.

After the test, I asked him when the album that we worked on together last year would be released. He surprisingly said it had already been released!

So I decided to introduce the album.

I used Peluso P-87 microphones for stereo miking on the grand piano, and Rode NT-55 microphones for the drum overheads and ambience positions. I also positioned two Shure SM57s on the top and bottom of the snare. I can’t quite remember, but I believe there was a rack for the kick microphone, so I likely used a Shure SM57 for that role as well.

There is also a peculiar musical instrument called the Saenghwang (a mouth organ). I remember that I installed a Peluso CEMC 6 over the head of the musician.

I used a Midas m32 console for both live mixing and recording simultaneously.

Yes, that’s all—maybe. It’s been about 9 months, so I can’t remember all the details accurately.

I only remember that the venue’s interior was made of concrete and brick, so it had a pretty long reverb time. Because of that, I struggled with the acoustics while mixing the live sound. However, in the recorded tracks, the piano actually sounded a bit too dry, so the artist wanted to add a huge amount of ambience—around -10 dB (whereas in popular music, ambience effects like reverbs are usually added around -30 to -20 dB).

These are unique and interesting tracks, so check them out..!

Meter part

As you know if you read my DIY hardware post series, about a month ago, I finished wiring and assembling all the components for my DIY audio hardware. When I powered it on, I immediately ran into two major problems. Only the left channel’s meter responded while the right channel’s meter remained completely dead, and there was no audio output at all.

I wasn’t even sure where to begin troubleshooting. After wiring up all the components for my DIY audio hardware, I ran into two major problems right away. First, only the left channel’s meter responded, while the right channel’s meter remained completely dead. Second, there was no audio output at all.

After spending so much time on the project without making any progress, I became so frustrated that I stopped working on it for a while. It honestly felt like burnout.

When I came back to it yesterday, I started thinking more logically. The meter was connected just before the THAT1646 output driver stage. If the left meter was responding correctly, that meant the entire signal path leading up to that point had to be functioning. In other words, the problem couldn’t be somewhere earlier in the circuit.

Following that line of reasoning, I first discovered that I had simply wired the right meter incorrectly. That explained why only the left meter had been moving.

With the meter issue solved, the only remaining suspect for the missing audio output was the THAT1646 itself. So I started digging into its documentation and pinout.

OPA 1612…!!

However, after replacing the devices, I discovered another problem. A significant amount of broadband noise was present, measuring higher than -75 dBFS across nearly the entire frequency spectrum.

I went back through the schematics and the datasheets, comparing my design with the recommended application circuits. That’s when I realized I had made a fundamental mistake: I hadn’t included the power-supply bypass capacitors for either the OPA1612 op-amps or the THAT1646 output drivers.

Looking back, it seems obvious. High-performance analog ICs like these rely on proper local decoupling to keep their supply rails stable and free from high-frequency noise. Without those capacitors placed close to the power pins, the circuit is far more susceptible to noise and instability.

So, despite thinking I was finally done troubleshooting, I ended up ordering yet another batch of components. Now I’m waiting for the capacitors to arrive before I can continue.

At this point, the project is slowly turning into Frankenstein’s monster. Every problem I solve seems to require another small modification to the hardware. Hopefully, these will be the last stitches before it finally comes to life.

That’s it for today.

Lately, I’ve barely had enough time to breathe between studying English and working on my research, so progress on this project has been a little slower than I’d like.

On the bright side, I recently picked up an SPL Vitalizer MK3, so you can look forward to a review of that in an upcoming post.

Thanks for reading, and I’ll see you in the next one!

I Got an Accept Decision from the Journal of the Audio Engineering Society

Hello! This is Jooyoung Kim, an audio engineer and music producer.

Last week, thankfully I got an acceptance from the Journal of the Audio Engineering Society (JAES).

I’ve moved it to My Sent Mail folder so it doesn’t get mixed up with other emails.

Previously, I submitted my work to other journals like IEEE Transactions on Consumer Electronics, the Journal of the Acoustical Society of America, Applied Acoustics, and Signal Processing. Having gone through the process of rejection, I really appreciate this positive decision from the JAES. In fact, JAES has always been the journal I dreamed of publishing in the most, which makes this acceptance even more meaningful to me.

Initially, I was concerned that my idea was perhaps too simple, so I conducted an extensive review of existing research to see if it had already been addressed. To my surprise, I discovered that there was a lack of research specifically covering this simple approach.

Since the template was updated, I had to go through the process of rebuilding my PDF files in the editorial manager multiple times. The long list of submission records reflects the effort and patience required to get everything formatted just right.

The review process took quite a bit of time. I submitted my initial draft on December 11, received the revision decision on April 15, and finally, the acceptance on May 18. If the result had been a rejection, I would have been devastated, but given the significant workload of reviewers who dedicate their valuable time to evaluate others’ work, I was quite satisfied with this timeline.

However, as an independent researcher, I am entirely self-funded. I worked hard to condense my manuscript to stay within the 10-page limit for free publication, but I unfortunately exceeded it. Now, I have to cover the page charges myself. With the recent sharp rise in the exchange rate between the Korean won and the U.S. dollar, these additional costs have become quite a financial burden.

Despite the financial challenge, I am more than happy to pay this fee because JAES is the journal I have always aspired to publish in. Seeing my work accepted there is truly one of the most rewarding moments of my research journey.

Once my paper is officially published, I will write a follow-up post to explain the research in more detail. Stay tuned for the next update!

Life Update (Apr 30, 2026)

Hello! This is Jooyoung Kim, an audio engineer and music producer.

I’ve been working on so many projects lately that I haven’t been able to post any articles to this blog. Some of them are currently in progress, so I’m just writing a simple life update today.

Let’s start!

Two weeks ago, I participated in a modular synthesizer seminar as a lecturer. I was already familiar with the principles of sound synthesis, and I own a semi-modular synth and a vocoder. However, it was my first time dealing with a full modular synthesizer (Eurorack standard). So, when I was preparing the seminar materials, I studied quite hard. Of course, it takes long time.

The organizer said they would send me some photos from the event, but I haven’t received them yet. Once they arrive, I’ll share the full story in more detail.

At the same time, I received a minor revision decision on my paper from the Audio Engineering Society. I was very grateful for the decision, but unfortunately, I also caught a bad cold. Because the reviewers suggested adding some simple measurements, I pushed myself to complete them, which made my cold even worse. I ended up having to lead the modular synth seminar while feeling quite ill.

Building the audio hardware—which I designed entirely from scratch—is now almost finished. Twisting all those wires and soldering the power lines was exhausting, but it has been quite rewarding. Now, I just need to solder the switches and potentiometers, and I’ll be all done. I’m really looking forward to it.

I also submitted my new research on deep learning related to audio hardware. I’ve been preparing this paper since last May, so it has been a year-long process. Personally, I don’t feel the experimental results were groundbreaking, but I submitted it anyway in hopes that it might be helpful to other researchers. I really hope it gets accepted!

I was selected for the ‘RE:SEARCH’ grant program by the Seoul Foundation for Arts and Culture, so I’ll be receiving some research funding. Since my proposed study includes listening tests, I’ve been busy designing the experiments, preparing documents for IRB approval, and conducting a literature review for the paper. These tasks are quite time-consuming, so I’ve been spending most of my time lately wrestling with all this writing.

The research funding will be released in May, which is also when the budget execution begins. Since the actual IRB review takes place in June, I have to submit all my documents by the end of May. The final approval usually doesn’t come out until early July, so I need to finalize the experiment design and paperwork very quickly. I think I’m going to have quite a headache dealing with all of this over the coming week.

With all these tasks piling up, I haven’t had a spare moment to focus on this blog. Once things start to wrap up—whether it’s finishing the hardware, getting my paper published, or receiving the photos from the modular synth seminar—I’ll make sure to post about them one by one.

Until then, I’ll see you in the next post!

Life Update (Mar 3, 2026)

Hello! This is Jooyoung Kim, an audio engineer and music producer.

This semester, I’m teaching at three different institutions: a junior college, a university, and a graduate school. Since they are located in different cities, I’ve been completely exhausted lately (I have to travel to Osan on Mondays, Daegu on Tuesdays, and Seoul on Wednesdays). Because I was preparing those class materials, my February passed in a blur.

Additionally, every Monday, Wednesday, and Thursday, I wake up at 6 a.m. for English speaking classes, and I spend my weekends taking several courses to prepare for the TOEFL. While I feel incredibly grateful and blessed, the lack of time for my own music-making is really weighing on me…

A research paper I submitted last year is currently under review. Meanwhile, I have completed another project involving a deep learning-based hardware compressor simulation and am now conducting listening experiments with participants. Tomorrow, I’ll meet last two subjects, and finally, it will be done. However, I’ve got to interpret the result and discuss what those things mean. It must take few days..

I chose a “TAKACHI” rack case to house my DIY audio hardware circuit and had an in-depth conversation with the manager. I really appreciate him. However, the enclosure was quite expensive due to the machining (drilling) process. I’ll talk all about that in another post.

Yap.. That’s all..! Quite simple, isn’t it? There was nothing interesting in my recent life. I must rest right now. Writing also makes me exhausted. See you in the next post..!